UW-Milwaukee Department of Mathematical Sciences presents,
Monday, March 30, 2015
2:00pm in EMS E408
Non-separability of a 3-manifold group:
A group G is residually finite if the intersection of all finite index normal subgroups of G is the trivial group. More generally, a subgroup H < G is separable if it is equal to the intersection of all finite index normal subgroups containing H. These properties have attracted a lot of attention in geometric group theory. I will give a short introduction to subgroup separability, emphasizing a topological viewpoint, before presenting a geometric proof of the non-separability of a 3-manifold group.
I will give a brief explanation of the relevance to my recent work on CAT(0) cubulations of tubular groups.